Dyna 400 - preamp??

[draftingmonkey]

I will be picking up a Dyna 400 amp this weekend and was wanting to find out what the era/date appropriate preamp from Dynaco would be for this amplifier? How about the same for a tuner to keep the whole setup as era appropriate Dynaco? Thanks for any info.

James

[dynaco_dan]

I will be picking up a Dyna 400 amp this weekend and was wanting to find out what the era/date appropriate preamp from Dynaco would be for this amplifier? How about the same for a tuner to keep the whole setup as era appropriate Dynaco? Thanks for any info.

James

Hi James;

If you are looking for a classic stock pre-amp, here is a small list.

Dynaco PAS-3X but due to higher collectibility, priced more expensive than it should be.

Dynaco PAT-4, usually under $50.00 on ebay.

Dynaco PAT-5, around $40.00 on ebay, or the later improved PAT-5 Bi-Fet.

Hafler DH-100 or DH-101.

My favourite, Crown IC-150 or the later IC-150A.

Carver C-1.

There is numerous other pre-amps that I have never tried.

I have several service tips for the Dynaco 400 amplifier, James.

Does yours have the fan and meters?

There was at least 4 - Dynaco 400 basic amplifier versions, maybe even more that I know of.

There was two different switches for the power on/off.

There was a phase 1 and phase two also.

[draftingmonkey]

Vern,

Thanks for the info. I didn't know if Dynaco had a particular pre-amp they had designed in conjunction with the 400. I know many manufacturers did.

Currently I have:

PAS-2x with a ST-70

PAS-3 with a ST-70

PAT-4 with a ST-120

Maybe will look for a PAT-5 for the 400 and keep it in the Dynaco family.

Thanks again. Will talk to you later.

James

[dynaco_dan]

Vern,

Thanks for the info. I didn't know if Dynaco had a particular pre-amp they had designed in conjunction with the 400. I know many manufacturers did.

Currently I have:

PAS-2x with a ST-70

PAS-3 with a ST-70

PAT-4 with a ST-120

Maybe will look for a PAT-5 for the 400 and keep it in the Dynaco family.

Thanks again. Will talk to you later.

James

Hi again James;

What you listed is very old and obsolete now, please package it all immediately, real well and pre-pay shipping to me to make you feel more modern. LOL LOL

When I wrote the earlier reply I did not have my list in my hand, so here it goes.

The PAS-3X was introduced in 1960.

Being tube it may have a softness to the the sound that may or may not be to your liking with the Dynaco 400 s/s amplifier.

I would not go out an buy one just because I listed it, unless you also have a Dynaco Stereo 70 or 2 - Mark 3's for it.

The Stereo 120 came out in 1966 and the Pat-4 came out in 1967.

The Stereo 400 came out in 1972 and the PAT-5 came out in 1974.

The PAT-5 Bi-FET came out in 1977.

The combination of Stereo 120 and PAT-4 was a perfect match at that time.

As you can see the PAT-5 came out 7 years after the PAT-4.

There was an improvement but the PAT-4 still holds it's own against some newer pre-amps, sound wise.

The PAT-5 Bi-FET was another improvement, at an even higher price.

Technology and engineering changes progressed in each model.

The PAT-5 was the first and more for the, Stereo 400, with it's speaker switching and power switching ability for the large powered amplifier.

I would personally not want my non-availabe pre-amp switch to turn on my super amps, I don't care how heavy duty it is.

Sadly, I have not watched the pre-amp sales as I should have to give you better pricing ideas.

I use a, cheap, being Scottish, as in $5.00 CDN, switched power bar to turn my Crown DC-300A and Dynaco 400 amplifiers on, separately.

The two or three position un-lighted Dynaco amp power switch is no longer available, so I leave it turned on, to the right position, and use the power bar switch with a quick snap of the wrist.

The original Crown power switch was neon lighted and was about $25.00+ direct from Crown about 10 years ago.

The Crown replacement switch that I received was not lighted.

Usually turning on these super power amps burns out the amplifiers switch contacts pretty quickly.

The Dynaco 400 also has a 10 amp circuit breaker instead of a glass power fuse.

There is some service information available.

To sum up, James, the later the pre-amp the better the apparent technology available.

I would still consider, Crown IC-150 or 150A, Carver, or Haflers as good value, depending on price and condition.

A slightly scratched Crown IC-150 at $50.00 is a steal, over $150.00 not a deal.

A stock PAT-4 at $100.00 is way too much to pay in my opinion, at $40.00 great value.

There is other pre-amps, I am certain that other members have in their favourite systems they will share with you and us.

Good luck, James.

[dynaco_dan]

Hi again James;

The two or three position un-lighted Dynaco amp power switch is no longer available, so I leave it turned on, to the right position, and use the power bar switch with a quick snap of the wrist.

Usually turning on these super power amps burns out the amplifiers switch contacts pretty quickly.

The Dynaco 400 also has a 10 amp circuit breaker instead of a glass power fuse.

There is some service information available.

There is other pre-amps, I am certain that other members have in their favourite systems they will share with you and us.

Good luck, James.

Hi again James;

I forgot to mention something I see a lot of, written that is, James, the front Littlefuse speaker fuseholder covers tend to break, apparently.

You cannot install the front fuseholder cover without a fuse in it, or it needs to be broken to remove it again.

I see red coloured covers for sale on ebay, once in a while, even though the stock colour is black.

I've never broken mine but you never know.